Measuring varroa

[Cuckmere couple]

Worth it or just treat routinely?

 

[Beefriendly]

Up to you really.
The difficulty I see, when you have quite a few hives, is the time to do the counting can become disproportionate to the time taken to do the treatment. Drop counts are not an accurate method of checking for varroa numbers, you need to do sugar/alcohol rolls.
You can tell from that, that I'm a treat regardless of numbers of varroa's...but now use your monitoring boards to assess the success of the treatment by the number of dead varroa that drop through...this doesn't now need to be accurate but gives you confidence your treatments have worked when you find 1000's of dead varroa a few days after treatment (time does depend on treatment method e.g Amitraz?? Strips being quite slow acting)... I find this checking it has worked to be the important bit.
There are strange goings on in hives with varroa.....

 

[Cuckmere couple]

sort of exactly my thinking

read the NBU 44 pages on varroa today and ended up thinking...it may be helpful to know high versus medium infestation as that WOULD probably affect your tretment, but, a clear take home is that treatment is necessary and here to stay for time being

so

my thinking was probably just treat (and confirm success through dead mite drop) but routine treatment is hardly likely to be contra indicated by counting

 

[mike99]

I don't have any depth of knowledge on this subject. I treat my colony and noted that there was a significant increase in drops afterwards. I also did the dribble method and again there was an increase in drop. My fear is whether the Varroa can become immune eventually to the treatments just like Head Lice has become immune to the popular treatments available?

 

[Curly green fingers]

Personally I do sugar roll tests with a sample of bee's four times a year no alcohol as using sugar is much kinder for the bee's .
I will do my first one in April. I will say that this is done as part of a none treatment scheme that I am now a part of.
Evidence that I've been shown is telling me that over treatment of mitecides is affecting queen and drone fertility .
So in my opinion just treating because it's the time of year to do it or you think they need treating is the wrong thing to do for the future of honey bees .

I wanted to add that the scheme I'm in is only on selected colony's that are more than 70% Amms
And the sugar roll is integrated with more observations than just the sugar roll test. FYI...

 

[B+.]

Unless your bees have been selected for their ability to manage varroa, you should probably continue to treat.
The natural mite drop test is valid at the start of the season, when you are only counting phoretic mites. However, as the season progresses (i.e. as they get more sealed brood) this becomes increasingly inaccurate. That is when you switch to sampling worker bees from the supers (soap/alcohol/sugar test).
The 2019 season appears to be starting early here in Bedfordshire. I did a quick inspection in my test apiary yesterday and most, if not all, had some sealed brood already.

 

[For want of a better word]

Personally I do sugar roll tests with a sample of bee's four times a year no alcohol as using sugar is much kinder for the bee's .

Plural of bee is bees..... no problem with alcohol... keep treating as you do not want to produce a varroa bomb!

 

[domino]

I do alcohol washes, works a treat for me.

 

[Repwoc]

I do alcohol washes, works a treat for me.

Do you use meths or do you have a source of absolute ethanol?

 

[Eyeman]

Unless your bees have been selected for their ability to manage varroa, you should probably continue to treat.
The natural mite drop test is valid at the start of the season, when you are only counting phoretic mites. However, as the season progresses (i.e. as they get more sealed brood) this becomes increasingly inaccurate. That is when you switch to sampling worker bees from the supers (soap/alcohol/sugar test).
The 2019 season appears to be starting early here in Bedfordshire. I did a quick inspection in my test apiary yesterday and most, if not all, had some sealed brood already.

That's when you go wrong. You need to sample where most mites are located and that is over unsealed brood. It also gives consistent results. Have tried supers whilst doing brood and rarely get a single mite from the supers yet plenty from the brood.

 

[Eyeman]

Most will not sample after treatment then wonder why their bees didn't make it till spring. Surprising how treatments can be in ineffective if you sample before and after.

 

[Eyeman]

Do you use meths or do you have a source of absolute ethanol?

Isopropyl alcohol (rubbing alcohol)- easy to obtain in bulk and best used neat.

 

[Curly green fingers]

That's when you go wrong. You need to sample where most mites are located and that is over unsealed brood. It also gives consistent results. Have tried supers whilst doing brood and rarely get a single mite from the supers yet plenty from the brood.

Mainly nurse bee's? For samples